Singapore 1B Unit 31 Beyond - help

[alydar]

We're struggling a little in this area of math - both me and DS. Ex.- 16-8 = 8 and 46-8 = ? It seemingly wants the child to think of it in these terms: 46 broken down into 16 and 30, then subtract 8. But honestly, both DS and I are scratching our heads here. I'm trying to figure out how to explain "why" it needs to be broken up into 16 and 30 (why not 6 and 40? or 26 and 20?) and then how to work the problem from there.

Of course, alot of my difficulty comes from not learning math this way so I'm having a hard time understanding it myself. This is definitely a concept that DS is going to need extra work on but I don't really know how to help him here. Therefore, I come here seeking wonderful advice.

[my3sons]

We're struggling a little in this area of math - both me and DS. Ex.- 16-8 = 8 and 46-8 = ? It seemingly wants the child to think of it in these terms: 46 broken down into 16 and 30, then subtract 8. But honestly, both DS and I are scratching our heads here. I'm trying to figure out how to explain "why" it needs to be broken up into 16 and 30 (why not 6 and 40? or 26 and 20?) and then how to work the problem from there.

Of course, alot of my difficulty comes from not learning math this way so I'm having a hard time understanding it myself. This is definitely a concept that DS is going to need extra work on but I don't really know how to help him here. Therefore, I come here seeking wonderful advice.

Singapore math tries to give a mental math line of thinking to solve problems such as these. It really is showing a mental way to use what you already know to solve a harder problem mentally, so you don't have to write it all out and end up carrying or borrowing numbers.

In the problem you gave here as an example, the line of thinking is "I already know 16-8 = 8. I can use that to help me quickly solve 46 - 8. I can think of '46' as '16' and '30'. Now I can just take 16 - 8 = 8 (which I originally already knew well), and add the '30' back on to get '38'.

When I first introduce a concept like this, I like to make a bracket under the '46' on the paper to show we are thinking of it as '16' and '30'. Then we just do the 16 - 8 = 8, write the 8, cross of the 16, and add the 30. Sounds complicated, but it's really not, and the good news is it gets easier and easier. The bracket making is soon a thing of the past, as they are doing this in their head. In fact, I am even thinking of math like this now and solving problems mentally that I always previously had to write down on scratch paper. I'd encourage you to stick with this mental math line of thinking - it really is a great way to do math, and helps our kiddos be able to solve problems with shortcuts that encourage excellent math number sense. HTH!

In Christ,
Julie

[alydar]

Thank you Julie so much for that response. It does help me understand a bit better now that you've explained it. I think I'm going to make out some extra problems for DS (and me!) to practice with. I think it's soooo cool how my kids are learning things I never did at their age and also in a way that is so much better. HOD is so wonderful!

[deltagal]

We worked on the same problems today with my 7 yo!! You'll visit it over and over again, so lots of opportunity to practice.

[alydar]

We worked on the same problems today with my 7 yo!! You'll visit it over and over again, so lots of opportunity to practice.

Get outta here! Thanks for the reassurance!

[KristinBeth]

Wow, I don't want to hijack your thread, but that sounds so complicated I don't know if I can do Singapore 1st grade math myself, let alone teach it. You ladies are impressing me.

[Dustybug]

Wow, I don't want to hijack your thread, but that sounds so complicated I don't know if I can do Singapore 1st grade math myself, let alone teach it. You ladies are impressing me.

I'm with you here. I have all the stuff for Singapore next year with Beyond, but I'm had anxiety over it from the beginning.

[psreit]

My dd will soon be to that. What if she doesn't know 16-8 in her head? She can do it with manipulatives, but she doesn't have the subtraction in her head, yet. Are those problems supposed to be done without manipulatives?

[Gwenny]

Definitely let them use manipulatives. I believe Carrie said up until book 3 even. I have one who still uses manipulatives and is a couple of pages from finishing 1B and another finishing 1A and he almost never does, he does a lot in his head, hardly pays attention to the pictures even. The one in 1B uses them way less already. She would use them on the simplest problems and I was worried that she was not going to get it. About 10 or so pages ago, things seemed to click and she is zipping through with no manipulatives. I'm sure in the next book, 2A, she might need them again.
I've used a bunch of different math programs over the last 18 years of homeschooling, this is my first time with Singapore.. I love love it. I love Carrie's activities also.

[psreit]

Thanks, Nancy. I just know we will be using them for a while. This is an area of struggle for my dd.

Yesterday we did Unit 29, Day 1. She knows how to count to 100, but I should have just let her use a 100 chart to do these exercises. She had some difficulty putting these numbers in order, but the biggest problem was telling me what the smallest and lowest number was. For example, in 58, 60, 72, 95, when I asked her what the smallest number was, she pointed to 60. I'm not sure if it because there is a zero in it or what. All, I know is that she could not pick out the smallest and greatest numbers. I know from doing some research, that she has some visual perceptual problems. What I finally did for one of them was make a number line with the four number included and had her pick out each number. Then she was able to show me the smallest and the greatest. But looking at just the four together, she couldn't do it. She REALLY got confused when they started with the greatest number first. She would think because it was first, that it was the smallest. Without that number line, she was clueless. I made the mistake of trying to 'explain' things, rather than just using the number line and letting it go at that. Then we end up with meltdowns.

I don't want to push her through the books just to keep up with the guides. We are off schedule a little in Beyond. I want to finish 1B during the summer. I was planning to start Bigger half speed, so maybe I should do math half speed as well, if we run into problems like this. There are some parts of math she does get, but I'm afraid we are nearing some obstacles. She will be 9 next week and going into 3rd, so it will just mean getting PM2 finished sometime in 4th grade. I think there may be some skill areas we will need to stop and focus on for a while.

Some areas of difficulty for children with visual perceptual problems are spatial relationships such as distance, size, shape, and how things fit together as a whole, estimating passage of time, just to name a few. If anyone has any unique strategies for children with this struggle, please share.

[MomtoJGJE]

Different kids will pick up "basic" facts faster (even without using flashcards or working specifically to learn them)

My oldest has mult and div down pat... she knows some addition and subtraction without thinking, and is quickly getting better at it. Sometimes she still will pick up manipulatives, and I'm really working on her to think about it before she automatically counts on her fingers. She still doesn't get how to break down numbers to make it easier.

My second is just now starting 1B and knows her addition and subtraction better than the oldest, and is figuring out mult on her own. She really doesn't like using manipulatives, even the pictures in the book... even when she's supposed to add to or cross out pictures. She GETS the types of problems in the OP... she does that even for like 12-5 and all on her own.

[deltagal]

Although there is a message board for Singapore, I'm always so delighted when people post their Singapore questions here. I think it is so helpful and affirming to see when people are having challenges and successes with the Singapore method. And it helps encourage us all in the journey. So, thanks for the original post. It's so good to see people talking about Singapore. Let's keep the conversation going....

[alydar]

Regarding manipulatives, I do let DS use them as needed - a measure tape for a number line, almonds, goldfish, a 100 chart, a tens and ones chart.....whatever helps him "get it". I figure this is the time to lay a good foundation, not a time to rush. And he's so hands-on and visual so the manipulatives are a big help right now. Plus, I know he's starting to remember some number facts - simple addition & subtraction stuff - when he spouts off answers to DD's math questions. Yay!

Thanks again, Julie, for your explanation! I was really thinking about that last night as I was trying to sleep and it is making more sense to me how the program is trying to get little minds to think. Now, I feel I can better explain it to DS and help him understand. I do really like the Singapore program so far and am pleased with the progress my kids are making in it. And I totally agree with how awesome the activites are that go along with the lessons! They make the biggest difference and at the same time make it easy to teach the concept.